/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.catalina.core;

import org.apache.catalina.Context;
import org.apache.catalina.LifecycleState;
import org.apache.catalina.Wrapper;
import org.apache.catalina.util.ParameterMap;
import org.apache.tomcat.util.res.StringManager;

import javax.servlet.MultipartConfigElement;
import javax.servlet.ServletRegistration;
import javax.servlet.ServletSecurityElement;
import java.util.*;

public class ApplicationServletRegistration
		implements ServletRegistration.Dynamic {

	/**
	 * The string manager for this package.
	 */
	private static final StringManager sm =
			StringManager.getManager(Constants.Package);

	private Wrapper wrapper;
	private Context context;

	public ApplicationServletRegistration(Wrapper wrapper,
	                                      Context context) {
		this.wrapper = wrapper;
		this.context = context;

	}

	@Override
	public String getClassName() {
		return wrapper.getServletClass();
	}

	@Override
	public String getInitParameter(String name) {
		return wrapper.findInitParameter(name);
	}

	@Override
	public Map<String, String> getInitParameters() {
		ParameterMap<String, String> result = new ParameterMap<String, String>();

		String[] parameterNames = wrapper.findInitParameters();

		for (String parameterName : parameterNames) {
			result.put(parameterName, wrapper.findInitParameter(parameterName));
		}

		result.setLocked(true);
		return result;
	}

	@Override
	public String getName() {
		return wrapper.getName();
	}

	@Override
	public boolean setInitParameter(String name, String value) {
		if (name == null || value == null) {
			throw new IllegalArgumentException(
					sm.getString("applicationFilterRegistration.nullInitParam",
							name, value));
		}
		if (getInitParameter(name) != null) {
			return false;
		}

		wrapper.addInitParameter(name, value);

		return true;
	}

	@Override
	public Set<String> setInitParameters(Map<String, String> initParameters) {

		Set<String> conflicts = new HashSet<String>();

		for (Map.Entry<String, String> entry : initParameters.entrySet()) {
			if (entry.getKey() == null || entry.getValue() == null) {
				throw new IllegalArgumentException(sm.getString(
						"applicationFilterRegistration.nullInitParams",
						entry.getKey(), entry.getValue()));
			}
			if (getInitParameter(entry.getKey()) != null) {
				conflicts.add(entry.getKey());
			}
		}

		// Have to add in a separate loop since spec requires no updates at all
		// if there is an issue
		if (conflicts.isEmpty()) {
			for (Map.Entry<String, String> entry : initParameters.entrySet()) {
				setInitParameter(entry.getKey(), entry.getValue());
			}
		}

		return conflicts;
	}

	@Override
	public void setAsyncSupported(boolean asyncSupported) {
		wrapper.setAsyncSupported(asyncSupported);
	}

	@Override
	public void setLoadOnStartup(int loadOnStartup) {
		wrapper.setLoadOnStartup(loadOnStartup);
	}

	@Override
	public void setMultipartConfig(MultipartConfigElement multipartConfig) {
		wrapper.setMultipartConfigElement(multipartConfig);
	}

	@Override
	public Set<String> setServletSecurity(ServletSecurityElement constraint) {
		if (constraint == null) {
			throw new IllegalArgumentException(sm.getString(
					"applicationServletRegistration.setServletSecurity.iae",
					getName(), context.getName()));
		}

		if (!context.getState().equals(LifecycleState.STARTING_PREP)) {
			throw new IllegalStateException(sm.getString(
					"applicationServletRegistration.setServletSecurity.ise",
					getName(), context.getName()));
		}

		return context.addServletSecurity(this, constraint);
	}

	@Override
	public Set<String> addMapping(String... urlPatterns) {
		if (urlPatterns == null) {
			return Collections.emptySet();
		}

		Set<String> conflicts = new HashSet<String>();

		for (String urlPattern : urlPatterns) {
			String wrapperName = context.findServletMapping(urlPattern);
			if (wrapperName != null) {
				Wrapper wrapper = (Wrapper) context.findChild(wrapperName);
				if (wrapper.isOverridable()) {
					// Some Wrappers (from global and host web.xml) may be
					// overridden rather than generating a conflict
					context.removeServletMapping(urlPattern);
				} else {
					conflicts.add(urlPattern);
				}
			}
		}

		if (!conflicts.isEmpty()) {
			return conflicts;
		}

		for (String urlPattern : urlPatterns) {
			context.addServletMapping(urlPattern, wrapper.getName());
		}
		return Collections.emptySet();
	}

	@Override
	public Collection<String> getMappings() {

		Set<String> result = new HashSet<String>();
		String servletName = wrapper.getName();

		String[] urlPatterns = context.findServletMappings();
		for (String urlPattern : urlPatterns) {
			String name = context.findServletMapping(urlPattern);
			if (name.equals(servletName)) {
				result.add(urlPattern);
			}
		}
		return result;
	}

	@Override
	public String getRunAsRole() {
		return wrapper.getRunAs();
	}

	@Override
	public void setRunAsRole(String roleName) {
		wrapper.setRunAs(roleName);
	}

}
